The present invention relates to the tuning of optical devices, and more particularly, to the tuning of optical devices including birefringent elements, such as interleavers and deinterleavers.
Optical devices and components and associated networks generally have greater bandwidth than wired components and networks. One of the technologies that allows optical components and networks (WDM), which provides increased capacity on fiber optic cables. Dense wavelength division multiplexing (DWDM) is a further improvement of WDW.
WDW and DWDW technologies combine multiple optical signals into a single fiber by transporting different signal on different optical wavelenghts or channels. Interleaving and deinterleaving can be accomplished in many ways. As channel spacing becomes denser, optical components generally must become smaller and more precisely manufactured. For some applications, the precision required for acceptable performance exceeds available manufacturing tolerances. For these applications what is needed is a technique for tuning optical devices to greater precision than through manufacturing specifications and tolerances alone.
Accordingly, the present invention relates to a method of tuning an optical component, of the type including at least one birefringent subcomponent, comprising the steps of:
determining a frequency response of the optical component; and
modifying the frequency response of the optical component with a tuning plate having a thickness and an optical axis orientation;
wherein the tuning plate has a small birefringence as compared to at least one of the birefringent subcomponents.
Another aspect of the present invention relates to an apparatus for tuning an optical component, of the type including at least one birefringent subcomponent, comprising:
means for determining a frequency response of the optical component; and
means for modifying the frequency response of the optical component with a tuning plate having a thickness and an optical axis orientation;
wherein the tuning plate has a small birefringence as compared to at least one of the birefringent subcomponents.